android_type_text

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full behavioral burden, yet it does not say whether existing text is replaced or appended, what happens if no field is focused or an IME is blocked, or what errors/results to expect. For a mutating input action this is a notable gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

One tight sentence with the action and target front-loaded and no filler. It is appropriately sized for a single-parameter tool, though it stops short of adding the extra operational detail that would make the brevity fully earned.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The core action is complete for a simple one-parameter tool, but with no annotations and no output schema the description omits focus prerequisites and failure/return behavior. Adequate but leaves clear gaps for an agent invoking it blind.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The single parameter has full schema description coverage ("The text string to type") and there is nothing to clarify about format, so the baseline of 3 applies. The description adds no semantics beyond what the schema already provides.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (type) and resource (a string of text) plus the target (currently active input field), which cleanly separates it from android_click_by_text or android_press_key. It does not explicitly name any sibling, but the action is unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase "currently active input field" implicitly signals the prerequisite that a field must already be focused, but there is no explicit when-to-use, when-not-to-use, or pointer to alternatives (e.g., android_click_by_text to focus a field first). Usage is only inferable.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.